Abstract Previous studies aimed at exploring the SAR of C2-functionalized S-DABOs demonstrated that the substituent at this position plays a key role in the inhibition of both wild- type RT and drug-resistant enzymes, particularly the K103N mutant form. The introduction of a cyclopropyl group led us to the discovery of a potent inhibitor with picomolar activity against wild-type RT and nanomolar activity against many key mutant forms such as ...